The Experts below are selected from a list of 306 Experts worldwide ranked by ideXlab platform
Osamu Kitagawa - One of the best experts on this subject based on the ideXlab platform.
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N-C Axially Chiral Compounds with an ortho-Fluoro Substituent and Steric Discrimination between Hydrogen and Fluorine Atoms Based on a Diastereoselective Model Reaction
The Journal of organic chemistry, 2019Co-Authors: Asumi Iida, Mizuki Matsuoka, Hiroshi Hasegawa, Nicolas Vanthuyne, Daniel Farran, Christian Roussel, Osamu KitagawaAbstract:The fluorine atom is the second smallest atom; nevertheless, the ortho-Fluoro Group may lead to stable N-aryl atropisomers when the steric demand of the flanking substituents is large enough. 2-Alk...
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N–C Axially Chiral Compounds with an ortho -Fluoro Substituent and Steric Discrimination between Hydrogen and Fluorine Atoms Based on a Diastereoselective Model Reaction
Journal of Organic Chemistry, 2019Co-Authors: Asumi Iida, Mizuki Matsuoka, Hiroshi Hasegawa, Nicolas Vanthuyne, Daniel Farran, Christian Roussel, Osamu KitagawaAbstract:The fluorine atom is the second smallest atom; nevertheless, the ortho-Fluoro Group may lead to stable N-aryl atropisomers when the steric demand of the flanking substituents is large enough. 2-Alkyl-3-(2-Fluorophenyl)quinazolin-4-ones and 3-(2-Fluorophenyl)-4-methylthiazoline-2-thione were found to be the first N-aryl axially chiral compounds bearing an ortho-Fluoro Group whose enantiomers were isolated at ambient temperature. The reaction of alkyl halides with the anionic species prepared from 2-ethyl-3-(2-Fluorophenyl)quinazolin-4-one presenting an N−C axial chirality provided a model reaction for quantitative evaluation of the steric discrimination (slight difference of steric factor) between hydrogen and fluorine atoms. In the case of low steric demand (allylation reaction) no diastereoselectivity was detected, while in the case of high steric demand (isopropylation reaction) the diastereoselectivity became significant.
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N–C Axially Chiral Compounds with an ortho-Fluoro Substituent and Steric Discrimination between Hydrogen and Fluorine Atoms Based on a Diastereoselective Model Reaction
2019Co-Authors: Asumi Iida, Mizuki Matsuoka, Hiroshi Hasegawa, Nicolas Vanthuyne, Daniel Farran, Christian Roussel, Osamu KitagawaAbstract:The fluorine atom is the second smallest atom; nevertheless, the ortho-Fluoro Group may lead to stable N-aryl atropisomers when the steric demand of the flanking substituents is large enough. 2-Alkyl-3-(2-Fluorophenyl)quinazolin-4-ones and 3-(2-Fluorophenyl)-4-methylthiazoline-2-thione were found to be the first N-aryl axially chiral compounds bearing an ortho-Fluoro Group whose enantiomers were isolated at ambient temperature. The reaction of alkyl halides with the anionic species prepared from 2-ethyl-3-(2-Fluorophenyl)quinazolin-4-one presenting an N–C axial chirality provided a model reaction for quantitative evaluation of the steric discrimination (slight difference of steric factor) between hydrogen and fluorine atoms. In the case of low steric demand (allylation reaction) no diastereoselectivity was detected, while in the case of high steric demand (isopropylation reaction) the diastereoselectivity became significant
G P Suresha - One of the best experts on this subject based on the ideXlab platform.
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urea thiourea derivatives of quinazolinone lysine conjugates synthesis and structure activity relationships of a new series of antimicrobials
European Journal of Medicinal Chemistry, 2011Co-Authors: G P Suresha, R Suhas, Wethroe Kapfo, Channe D GowdaAbstract:Synthesis of a series of urea/thiourea/acetamide/sulphonamide derivatives of quinazolinones conjugated lysine has been reported. Structures of the products have been determined by standard spectroscopical studies. All the compounds have been screened for their antibacterial studies and structure-activity relationship has been developed. The activity profile revealed that the compounds containing urea and thiourea functionalities along with Fluoro Group have exerted a highly potent activity. Thus, the title compounds represent a novel class of potent antimicrobial agents.
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Urea/thiourea derivatives of quinazolinone-lysine conjugates: synthesis and structure-activity relationships of a new series of antimicrobials.
European journal of medicinal chemistry, 2011Co-Authors: G P Suresha, R Suhas, Wethroe Kapfo, D. Channe GowdaAbstract:Synthesis of a series of urea/thiourea/acetamide/sulphonamide derivatives of quinazolinones conjugated lysine has been reported. Structures of the products have been determined by standard spectroscopical studies. All the compounds have been screened for their antibacterial studies and structure-activity relationship has been developed. The activity profile revealed that the compounds containing urea and thiourea functionalities along with Fluoro Group have exerted a highly potent activity. Thus, the title compounds represent a novel class of potent antimicrobial agents.
Richard B. Rothman - One of the best experts on this subject based on the ideXlab platform.
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The dopamine, serotonin and norepinephrine releasing activities of a series of methcathinone analogs in male rat brain synaptosomes
Psychopharmacology, 2019Co-Authors: Bruce E. Blough, Ann M. Decker, Antonio Landavazo, Ojas A. Namjoshi, John S. Partilla, Michael H. Baumann, Richard B. RothmanAbstract:Rationale Novel synthetic “bath salt” cathinones continue to appear on the street as abused and addictive drugs. The range of subjective experiences produced by different cathinones suggests that some compounds have primarily dopaminergic activity (possible stimulants) while others have primarily serotonergic activity (possible empathogenics). An understanding of the structure activity relationships (SARs) of these compounds will help in assessing the likely behavioral effects of future novel structures, and to define potential therapeutic strategies to reverse any reinforcing effects. Objectives A series of methcathinone analogs was systematically studied for their activity at the dopamine and serotonin transporters. Compound structures varied at the aromatic Group, either by substituent or by replacement of the phenyl ring with a naphthalene or indole ring. Methods A novel, high-yielding synthesis of methcathinone hydrochlorides was developed which avoids isolation of the unstable free bases. Neurotransmitter transporter release activity was determined in rat brain synaptosomes as previously reported. Compounds were also screened for activity at the norepinephrine transporter. Results Twenty-eight methcathinone analogs were analyzed and fully characterized in dopamine and serotonin transporter release assays. Compounds substituted at the 2-position (ortho) were primarily dopaminergic. Compounds substituted at the 3-position (meta) were found to be much less dopaminergic, with some substituents favoring serotonergic activity. Compounds substituted at the 4-position (para) were found to be far more serotonergic, as were disubstituted compounds and other large aromatic Groups. One exception was the Fluoro-substituted analogs which seem to favor the dopamine transporter. Conclusions The dopaminergic to serotonergic ratio can be manipulated by choice of substituent and location on the aromatic ring. It is therefore likely possible to tweak the subjective and reinforcing effects of these compounds by adjusting their structure. Certain substituents like a Fluoro Group tend to favor the dopamine transporter, while others like a triFluoromethyl Group favor the serotonin transporter.
Ann M. Decker - One of the best experts on this subject based on the ideXlab platform.
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The dopamine, serotonin and norepinephrine releasing activities of a series of methcathinone analogs in male rat brain synaptosomes
Psychopharmacology, 2019Co-Authors: Bruce E. Blough, Ann M. Decker, Antonio Landavazo, Ojas A. Namjoshi, John S. Partilla, Michael H. Baumann, Richard B. RothmanAbstract:Rationale Novel synthetic “bath salt” cathinones continue to appear on the street as abused and addictive drugs. The range of subjective experiences produced by different cathinones suggests that some compounds have primarily dopaminergic activity (possible stimulants) while others have primarily serotonergic activity (possible empathogenics). An understanding of the structure activity relationships (SARs) of these compounds will help in assessing the likely behavioral effects of future novel structures, and to define potential therapeutic strategies to reverse any reinforcing effects. Objectives A series of methcathinone analogs was systematically studied for their activity at the dopamine and serotonin transporters. Compound structures varied at the aromatic Group, either by substituent or by replacement of the phenyl ring with a naphthalene or indole ring. Methods A novel, high-yielding synthesis of methcathinone hydrochlorides was developed which avoids isolation of the unstable free bases. Neurotransmitter transporter release activity was determined in rat brain synaptosomes as previously reported. Compounds were also screened for activity at the norepinephrine transporter. Results Twenty-eight methcathinone analogs were analyzed and fully characterized in dopamine and serotonin transporter release assays. Compounds substituted at the 2-position (ortho) were primarily dopaminergic. Compounds substituted at the 3-position (meta) were found to be much less dopaminergic, with some substituents favoring serotonergic activity. Compounds substituted at the 4-position (para) were found to be far more serotonergic, as were disubstituted compounds and other large aromatic Groups. One exception was the Fluoro-substituted analogs which seem to favor the dopamine transporter. Conclusions The dopaminergic to serotonergic ratio can be manipulated by choice of substituent and location on the aromatic ring. It is therefore likely possible to tweak the subjective and reinforcing effects of these compounds by adjusting their structure. Certain substituents like a Fluoro Group tend to favor the dopamine transporter, while others like a triFluoromethyl Group favor the serotonin transporter.
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Structure-activity relationships of substituted 1H-indole-2-carboxamides as CB1 receptor allosteric modulators
Bioorganic & medicinal chemistry, 2015Co-Authors: Thuy Nguyen, Nadezhda German, Ann M. Decker, Jenny L. Wiley, Brian F. Thomas, Terry P. Kenakin, Yanan ZhangAbstract:A series of substituted 1H-indole-2-carboxamides structurally related to compounds Org27569 (1), Org29647 (2) and Org27759 (3) were synthesized and evaluated for CB1 allosteric modulating activity in calcium mobilization assays. Structure-activity relationship studies showed that the modulation potency of this series at the CB1 receptor was enhanced by the presence of a diethylamino Group at the 4-position of the phenyl ring, a chloro or Fluoro Group at the C5 position and short alkyl Groups at the C3 position on the indole ring. The most potent compound (45) had an IC₅₀ value of 79 nM which is ∼2.5 and 10 fold more potent than the parent compounds 3 and 1, respectively. These compounds appeared to be negative allosteric modulators at the CB1 receptor and dose-dependently reduced the Emax of agonist CP55,940. These analogs may provide the basis for further optimization and use of CB1 allosteric modulators.
Asumi Iida - One of the best experts on this subject based on the ideXlab platform.
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N-C Axially Chiral Compounds with an ortho-Fluoro Substituent and Steric Discrimination between Hydrogen and Fluorine Atoms Based on a Diastereoselective Model Reaction
The Journal of organic chemistry, 2019Co-Authors: Asumi Iida, Mizuki Matsuoka, Hiroshi Hasegawa, Nicolas Vanthuyne, Daniel Farran, Christian Roussel, Osamu KitagawaAbstract:The fluorine atom is the second smallest atom; nevertheless, the ortho-Fluoro Group may lead to stable N-aryl atropisomers when the steric demand of the flanking substituents is large enough. 2-Alk...
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N–C Axially Chiral Compounds with an ortho -Fluoro Substituent and Steric Discrimination between Hydrogen and Fluorine Atoms Based on a Diastereoselective Model Reaction
Journal of Organic Chemistry, 2019Co-Authors: Asumi Iida, Mizuki Matsuoka, Hiroshi Hasegawa, Nicolas Vanthuyne, Daniel Farran, Christian Roussel, Osamu KitagawaAbstract:The fluorine atom is the second smallest atom; nevertheless, the ortho-Fluoro Group may lead to stable N-aryl atropisomers when the steric demand of the flanking substituents is large enough. 2-Alkyl-3-(2-Fluorophenyl)quinazolin-4-ones and 3-(2-Fluorophenyl)-4-methylthiazoline-2-thione were found to be the first N-aryl axially chiral compounds bearing an ortho-Fluoro Group whose enantiomers were isolated at ambient temperature. The reaction of alkyl halides with the anionic species prepared from 2-ethyl-3-(2-Fluorophenyl)quinazolin-4-one presenting an N−C axial chirality provided a model reaction for quantitative evaluation of the steric discrimination (slight difference of steric factor) between hydrogen and fluorine atoms. In the case of low steric demand (allylation reaction) no diastereoselectivity was detected, while in the case of high steric demand (isopropylation reaction) the diastereoselectivity became significant.
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N–C Axially Chiral Compounds with an ortho-Fluoro Substituent and Steric Discrimination between Hydrogen and Fluorine Atoms Based on a Diastereoselective Model Reaction
2019Co-Authors: Asumi Iida, Mizuki Matsuoka, Hiroshi Hasegawa, Nicolas Vanthuyne, Daniel Farran, Christian Roussel, Osamu KitagawaAbstract:The fluorine atom is the second smallest atom; nevertheless, the ortho-Fluoro Group may lead to stable N-aryl atropisomers when the steric demand of the flanking substituents is large enough. 2-Alkyl-3-(2-Fluorophenyl)quinazolin-4-ones and 3-(2-Fluorophenyl)-4-methylthiazoline-2-thione were found to be the first N-aryl axially chiral compounds bearing an ortho-Fluoro Group whose enantiomers were isolated at ambient temperature. The reaction of alkyl halides with the anionic species prepared from 2-ethyl-3-(2-Fluorophenyl)quinazolin-4-one presenting an N–C axial chirality provided a model reaction for quantitative evaluation of the steric discrimination (slight difference of steric factor) between hydrogen and fluorine atoms. In the case of low steric demand (allylation reaction) no diastereoselectivity was detected, while in the case of high steric demand (isopropylation reaction) the diastereoselectivity became significant